Preparation And Degradation Performance Of Supported Transition Metal Compound Catalysts

The rapid development of the dye industry has caused serious water pollution problems.Organic dyes in industrial wastewater are toxic to aquatic organisms,and humans.In this work,mesoporous silica nanoparticles and porous silica ball were used as carriers to load ruthenium-pyridine complex,Heme and CuS to get composite materials for dye degradation.Structure and morphology of the as-prepared composit catalysts were analyzed by nuclear magnetic resonance,elemental analysis,TEM,SEM,EDS,XRD,XPS and mapping.The degradation activities of composite materials for Methylene blue?MB?,Rhodamine B?RhB?and Congo red?CR?were also studied.The effects of H₂O₂,pH and catalyst on degradation efficiency were studied.At the same time,the recoverability of the catalyst was explored.The main research contents are as follows:?1?Two ruthenium-pyridine complexes?Ru[?Hctpy??bpy?Cl]Cl,Ru[?Hctpy??phen?Cl]Cl?were synthesized by solvothermal method,and mesoporous silica nanoparticles were prepared by sol-gel method and modified with amino groups.The Fenton-like degradation activity of ruthenium complexes to MB under visible light irradiation before and after loading was investigated,and the effects of the amount of H₂O₂ and catalyst on the degradation performance were investigated.The results show that visible light irradiation Ru[?Hctpy??phen?Cl]Cl has a good degradation effect on methylene blue under.Moreover,when Ru[?Hctpy??phen?Cl]Cl dosage was 10 mg and H₂O₂ dosage was 10 mL,the degradation effect of methylene blue?5 mg/mL?was the best.?2?Heme/SiO₂ catalysts were fabricated with amino-modified mesoporous silica nanoparticles and thiol-modified silica spheres as carriers respectively.The composite materials were characterized by infrared spectrum,ultraviolet visible spectrum,TEM,XRD and so on.The performance of two silica composites in the degradation of RhB and CR was studied.The effects of heme ratio,amount of H₂O₂,amount of catalyst and pH value on dye degradation were investigated.Results demonstrated that amino-modified mesoporous silica nanoparticles supported heme can not only effectively adsorb-degrade RhB under visible light irradiation,but also be effective under dark conditions.Through free radical capture experiments,it was found that·OH and·O₂^-act together in the degradation.Thiol-modified silica balls loaded with Heme can effectively remove RhB and CR under visible light.?3?Two kinds of CuS composites[CuS-SiO₂?A?,CuS-Si O₂?B?]were prepared hydrothermally using thiol-modified silica balos as support.The degradation activity of RhB and recyclability of CuS-Si O₂ were studied.The results show that both CuS composites can effectively degrade RhB,which can be reused six timeswith excellent degradation efficiency.In order to further improve the reusability,the two kinds of composite materials were coated with passivation solution.CuS-SiO₂?A?prepared by method A was used nine times after passivation treatment with a high degradation efficiency of 80%.